Gatto' di Patate

So many of my friends are good cooks, including Lilli, who originally hails from Salerno, about 30 miles south of Naples. She made the potato cake in the photo and gave it to me shortly before dinner tonight.
Boy, was I lucky to be in the right place at the right time. It's the ultimate comfort food all'Italiana. Think of mashed potatoes all dressed up and ready to show off. It's also a terrific party food too, to make ahead and bake later.
There are as many variations of this recipe as there are varieties of pizza. Some recipes call for adding bits of salami, some for ham, and some for both -- but you can omit the meat entirely if you like. You can also add provolone cheese in addition to the mozzarella, or pecorino instead of parmigiana. Like so many Italian cooks I know, Lilli keeps a lot recipes in her head, including this one. She did, however, spell out the basic ingredients, and I have approximated proportions in the recipe that follows.
The gatto' (accent on the second syllable) is a traditional Neapolitan recipe that takes its name from the French "gateau" or cake. If you make the mistake of accenting the first syllable, you've got yourself a potato cat, not a potato cake.

serves 6
2 lb. potatoes
1 egg
4 T. butter, plus more to grease the dish
1/2 cup parmigiano reggiano cheese, grated
3/4 cup mozzarella cheese, diced
1 cup cooked ham or salami, diced
2 T. Italian parsley, chopped
pinch of nutmeg

1/2 cup milk, or more as needed to keep the mixture from getting too hard
salt and pepper

bread crumbs
2 T. butter

Boil potatoes until tender and drain. Place the 4 T. butter into a bowl. Peel the potatoes and pass through a "ricer" or mash by hand directly into the bowl over the butter, so that the hot potatoes melt the butter. Cool for five minutes, then add the rest of the ingredients except the bread crumbs and the 2 T. butter. Mix it all together until blended. Grease the bottom of a pie plate or other oven-proof dish with butter and smooth the mixture into the container. Sprinkle bread crumbs on top and gently press down with a fork. Dab with bits of butter. Bake in a preheated 375 degree oven for about 45 minutes.